Weight Room Flooring I'm Building A Mud Room Within A Garage. How Should I Provide Support For A Floor That Is 18" Above Ground?

I'm building a mud room within a garage. How should I provide support for a floor that is 18" above ground? - weight room flooring

I am building a mud room in a garage. I wish that the floor of a bedroom in the garage. This means that the bottom of the mud room about 18 inches above the concrete floor be parked in the garage. I am the ceiling beams to two walls of the garage, but I'm worried how I will support the absence of the walls of the garage. I thought about using 2 "x8" support, 3 / 4 "parquet floor and 1 / 4" cement board for tile. Given the weight of the past (not to mention on the walls, not to mention) are connected, how can the necessary support? Use the same technique, with bridges and beams attached implementation supports up to 4 "x 4" posts that sit on concrete blocks? Am I crazy to think that I can use a double?